Get Help in an Emergency
The iPhone can quickly call 911 or emergency services as well as alert your emergency contacts if you need help. Once setup, you just need to press the side button five times fast and it will either start a countdown or directly call for help and text your emergency contacts.
With Auto Call set to on, the phone will start calling after a few seconds. When you set this up be careful as testing it repeatedly can accidentally call 911. Here's more on how to setup the iPhone 8 Emergency SOS feature.